A shifting mechanism refers to a mechanism that controls a transmission such that a shift finger is selected to be shifted to a shifting rail or is shifted to a gear in response to a motor unit being driven by a transmission control unit, whereby the clutch gear of a target gear engages with a relevant sleeve.
In the shifting mechanism, the position of the shift finger is controlled by a transmission control unit such that the shift finger can be correctly shifted to a target shift position through the actuation of a motor unit. When an error in the position of the shift finger occurs, the shift finger is not shifted to a correct position on the shift position, whereby a change of speed is not properly performed. Thus, due to defective engagement of shifting gears, shocks may occur, or the vehicle may not be properly driven.
In order to overcome these problems, it is required to correctly control the position of the shift finger. In this regard, a position sensor for measuring the position of the shift finger may be disposed on the shifting mechanism. However, this approach may not only increase the cost of the vehicle, but may also be problematic in terms of space utilization in a transmission having a complicated structure.
Thus, in order to determine a malfunction, such as an error in the value of the position of the shift finger, a Hall sensor disposed on the motor unit is used. A malfunction, such as an error in the value of the position of the shift finger, is determined based on an error signal received from the Hall sensor. However, meaningless error signals may be generated for a variety of reasons. When malfunctions are determined based on all of such error signals, an ordinary state may be diagnosed as a malfunction, which is problematic.
In order to compensate for this problem, an approach of filtering noises in error signals is used to determine a malfunctioning state when at least a preset number of error signals are counted. When error signals less than the preset number are accumulated, the shifting mechanism is determined not to be malfunctioning, but a defect in the engagement of the shifting gears may be caused when errors in the value of the position of the shift finger have accumulated.
The information disclosed in the Background of the Disclosure section is only for the enhancement of understanding of the background of the disclosure, and should not be taken as an acknowledgment or as any form of suggestion that this information forms a prior art that would already be known to a person skilled in the art.